error: expected `:`, found `(`
  --> $DIR/in-struct.rs:20:12
   |
LL |     Variant(&'_ u32), //~ ERROR
   |            ^ expected `:`

error[E0106]: missing lifetime specifier
  --> $DIR/in-struct.rs:16:9
   |
LL |     x: &'_ u32, //~ ERROR
   |         ^^ expected lifetime parameter

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0106`.